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Some innuendo, especially between Nobita and Shizuka (for example: seeing her in the bath or in panties). We often see if Nobita marries her or not in the future.

There are some discreet sexist stereotypes through the series.

Some characters, kids and adults and for both genders, are seen often wearing swimming suits.

In some episodes some kids fall in love. Some of the Doraemon's invents force temporaly to another person to love another.

In some episodes for the 1979 anime (and some movies), we can see frontal nudity from both sex, but mostly between children (Nobita's penis and Shizuka's breasts, for example). Butts are seen
from both 1979 and 2005 animes; in the latest, Nobita is occasionally seen naked, but nothing more than his butt is seen.

In an episode for the 2005 anime we can see an invent to see how a marriage will work. Nobita test it with Shizuka, but Suneo and Gian also suffers its effects and they want to kiss and cook for him respectively.

In another episode for the 2005 anime some doctors force Nobita to undress, and they make some photos that show how he cover his frontal parts during five seconds intermittently, but in another photo his butt can be seen during a second half.

In another episode for the 2005 anime, Shizuka let her skirt in Nobita's and she tells him not to bring it because people will "think bad". However, at the end of the episode, he chases her running through the streets trying to give her the skirt.

In another episode for the 2005 anime, Nobita wants to make a baby from any species and tells Shizuka if she wants to help him to make a baby. Shizuka reacts hitting him.